CMMVC8706E The command failed because the primary copy's autodelete flag is on, meaning type conversion is in progress.
Explanation
Changing the primary copy (using the chvdisk -primary command) is disabled when the primary copy's autodelete flag is on.
User response
Change the primary copy when the primary copy's autodelete is no.
Either wait for the type conversion to finish or cancel the process, if required, by using the rmvdiskcopy command.